Alibobo Rakhmatullaev's extra-time header sent Bunyodkor charging into the AFC Champions League semi-finals on Wednesday as he popped up to settle a pulsating 3-2 win over Adelaide United.

Later in Riyadh, South Korean side Ulsan Hyundai booked their semi-final ticket with a 4-0 win over Saudi Arabia's Al Hilal for a 5-0 aggregate win.

Brazilian striker Rafinha scored twice in three first half minutes, with headers from Kim Shin-wook and Lee Leun-ho completing the victory over the two-time Asian champions.

Ulsan now faces Bunyodkor in the last four after the Uzbek champions twice hit back from a goal down to force extra-time at 2-2 against Adelaide.

And it was midfielder Rakhmatullaev who nodded the crucial goal, six minutes from a penalty shoot-out, for a 5-4 aggregate victory over two legs.

Two weeks ago in Adelaide, the Central Asian side had fought back from a two-goal deficit to draw 2-2, and anyone expecting more fireworks at Tashkent's Jar Stadium was not to be disappointed.

Fans were still arriving at the open-ended venue when Iain Ramsay, fed by Dario Vidosic at the top left corner of the box, rifled a diagonal shot across Bunyodkor keeper Ignatiy Nesterov to make it 1-0 in just the third minute.

But Bunyodkor was soon back on terms when its captain Viktor Karpenko's curling cross was met on the penalty spot by a leaping Lutfulla Turaev, who stretched to aim a glancing header into the bottom corner on 13 minutes.

Adelaide remained under pressure and the talismanic Galekovic played hero when he twice stood up to one-on-one chances to Murzoev before half-time.

The frenetic tempo slowed briefly after the break but the tie came roaring back to life on 63 minutes when Adelaide substitute Jeronimo Neumann squeezed a shot off Nesterov and over the line with one of his very first touches.

Bunyodkor poured forward for its second equaliser of the night and Galekovic had to be on his toes when defender Jonathan McKain put him under pressure with a risky back pass.

Shortly afterwards, Akmal Shorakhmedov swung at a loose ball in the box and connected with a volley that somehow squirmed through the diving Galekovic to level the game again at 2-2 on 72 minutes.

With the aggregate score locked at 4-4 and extra-time looming, Adelaide received another body-blow when midfielder Fabian Barbiero was sent off for his second yellow card after a lazy challenge on Rakhmatullaev.

But Bunyodkor was also reduced to 10 men after the first 10 minutes of extra time when defender Anvar Gafurov saw red for a foul that floored Adelaide forward Vidosic.

Both sides were subdued in the tense closing stages but with six minutes to go, Turaev's probing cross found Rakhmatullaev on the far post and he planted his header past Galekovic for the winning goal, sparking wild celebrations.

Adelaide's Iain Fyfe was sent off in the dying seconds, reducing the visitors to nine men, but it was immaterial as the final whistle soon blew on a thrilling night in the Uzbek capital.

Saudi Arabia's two-time AFC Champions League winners Al Ittihad will play cross-Jeddah rivals Al Ahli in the other two-leg semi-final, starting on October 22.

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